> Subject: Re: [RFC PATCH v5 14/16] RDMA/irdma: Add ABI definitions
>
> On Fri, Apr 17, 2020 at 10:12:49AM -0700, Jeff Kirsher wrote:
> > From: Mustafa Ismail <mustafa.ismail@xxxxxxxxx>
> >
> > Add ABI definitions for irdma.
> >
> > Signed-off-by: Mustafa Ismail <mustafa.ismail@xxxxxxxxx>
> > Signed-off-by: Shiraz Saleem <shiraz.saleem@xxxxxxxxx>
> > ---
> > include/uapi/rdma/irdma-abi.h | 140
> > ++++++++++++++++++++++++++++++++++
> > 1 file changed, 140 insertions(+)
> > create mode 100644 include/uapi/rdma/irdma-abi.h
> >
> > diff --git a/include/uapi/rdma/irdma-abi.h
> > b/include/uapi/rdma/irdma-abi.h new file mode 100644 index
> > 000000000000..2eb253220161
> > --- /dev/null
> > +++ b/include/uapi/rdma/irdma-abi.h
> > @@ -0,0 +1,140 @@
> > +/* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR
> > +Linux-OpenIB) */
> > +/*
> > + * Copyright (c) 2006 - 2019 Intel Corporation. All rights reserved.
> > + * Copyright (c) 2005 Topspin Communications. All rights reserved.
> > + * Copyright (c) 2005 Cisco Systems. All rights reserved.
> > + * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved.
> > + */
> > +
> > +#ifndef IRDMA_ABI_H
> > +#define IRDMA_ABI_H
> > +
> > +#include <linux/types.h>
> > +
> > +/* irdma must support legacy GEN_1 i40iw kernel
> > + * and user-space whose last ABI ver is 5 */ #define IRDMA_ABI_VER 6
> > +
> > +enum irdma_memreg_type {
> > + IW_MEMREG_TYPE_MEM = 0,
> > + IW_MEMREG_TYPE_QP = 1,
> > + IW_MEMREG_TYPE_CQ = 2,
> > + IW_MEMREG_TYPE_RSVD = 3,
> > + IW_MEMREG_TYPE_MW = 4,
> > +};
> > +
> > +struct irdma_alloc_ucontext_req {
> > + __u32 rsvd32;
> > + __u8 userspace_ver;
> > + __u8 rsvd8[3];
> > +};
> > +
> > +struct i40iw_alloc_ucontext_req {
> > + __u32 rsvd32;
> > + __u8 userspace_ver;
> > + __u8 rsvd8[3];
> > +};
> > +
> > +struct irdma_alloc_ucontext_resp {
> > + __aligned_u64 feature_flags;
> > + __aligned_u64 db_mmap_key;
> > + __u32 max_hw_wq_frags;
> > + __u32 max_hw_read_sges;
> > + __u32 max_hw_inline;
> > + __u32 max_hw_rq_quanta;
> > + __u32 max_hw_wq_quanta;
> > + __u32 min_hw_cq_size;
> > + __u32 max_hw_cq_size;
> > + __u32 rsvd1[7];
> > + __u16 max_hw_sq_chunk;
> > + __u16 rsvd2[11];
> > + __u8 kernel_ver;
>
> Why do you need to copy this kernel_ver from i40iw?
> Especially given the fact that i40iw didn't use it too much
> 120 static int i40iw_alloc_ucontext(struct ib_ucontext *uctx,
> 121 struct ib_udata *udata)
> <...>
> 140 uresp.kernel_ver = req.userspace_ver;
>
Its used to pass the current driver ABI ver. to user-space so that
there is compatibility check in user-space as well.
for example: old i40iw user-space provider wont bind to gen_2 devices
by checking the kernel_ver and finding its incompatible. It will bind with
gen_1 devices though..
